Hi Raidegas. Thanks! I caulked it with special waterproofing caulk called Sikaflex, but there's many others that will do, as long as they stick well and are of good quality. I also put short screws on the 6 holes that the panel came with, onto the fibreglass roof, and then caulked over them as well. I think if it is properly caulked underneath of the panel and all the way on their sides, you don't need screws. Rather, I think you would have trouble removing them! The panels do curve a lot withouth damage.

Thanks! True... I lived in California and couldn't find any; now back in Spain I jumped at the chance!

Hi Maggie, Thanks very much! If not ideas, I'm glad I brought you good memories!